Molding-machine.



-w. H. HOI'MANN.

MOLDING MACHINE. APPLICATION runn 920.16, 1907,

Patented Apr. 20,1909.

I Will/0'17 fi o/M01112,

' certain. new and useful Molding Machine, of-

' which the following isa-f-ull, clear, and exact description. p I v hisinventionrela'tes to the molding of sand in foundries. 1 The princi al objects of the invention are to provide a evice or'this purpose in which the sand shall be packed or compressed in 15 such a 'manner that it will be'tucked in around the pattern on all sides thereof, this acpomplished by an improved means for securing a re ressive compression of the sand, preferab y rst lengthwise of the flask in one "direction and then back along. the flask in the other direction; also to provide effic ent mechanism for accomplishing this result in-a simple manner by the use of a heavy cylindrical roller, the body ortion of wh1c is smooth-surfaced and uni 'orm from endto e'ndforcom'p'ressin the sand by its own .wei ht and supporte flaskw e compressingit. y

The invention also comprises improved means for operating the roller and adjustable means located outside the flaskfor supporting the rollerindependently of the flask when not in operation, whereby the roller can be entirely by fthe brought substantiallfto' the. level of the top thereof ;-al 'so means adapted to be located in theflask for preventing the sand. from being packed too'hard over the rojecting portions 'ofthe' ttern'; and genera ly to improve and sim l' 1 the-construction of sand rammingror- Em devices.

J *Furt cl-objects and advanta 'vention appeanhereinafter.

Reference is to be had to the accompanydrawing, in 'WhiC-ll -f' in Iligure 1' lsjaside elevation of a m' chine embodying this invention; Fig. 2 is aransverse sectlona'l view of the same showing a preliminary operation without the roller; ig. 3is a view similar to Fig. 2, showing the partsflin the osition occupied while the sand s being'pa'c ed and Fig, 4 is a-similarviewh lrawn, the roller showing. thepattern' being located at-t 'h'e'e ofthe fiask.

Alt hbughseveral'devires have been sugwhich rollers'are tobe employedfor a d '9 a la he-Primes 1K y Specification of Letters Patent..- 7 Application-filed December 10,1907.

,which is relatively highly paid, and is a very ges of the in 4 1 I the bottom boarder stripping late M on the UNITED STATES PATENT. oF-FrcE:

: I i I if MbLDING-ifllliilil OVRKiZN.

ra'tentod April 20, 1909.

1 Serial No. 409,721. v

has heretofore been the general practice in ramming sand around patterns for the pro duction of castings to employ either hand rammers or vertically moving rammers oporated by pneumatic, hydraulic or,electric'motive ower. In the use of these devices it has een found that the pick rammer which has a comparatively small-pressing or ramming surface, tends to create s ot's of va- 'rious compressed'consistencies an when the butt rammer which has a greater ressing or ramming surface" is substantial y used upon sand which has been pick rammed, the consistency of the whole-mass of sand surrounding the pattern is uneven and 'notcalculated to procure the best results when the.

molten metal is flowed into the mold.

In the use of the various vertically operated power rammers, the sand frequently fails to fill the crevices and interstices of the pattern, when such exist, and through such failure, imperfect molds are often obtained, and many castings have to be thrown away in daily foundry practice. In both cases also, it is of course necessary to exercise extreme ,care to secure good results, so that all methods of rammin which are in common use involve the employment of skilled labor slow process, whilethe power rammers are; moreimperfectin results and a power plant of some kind is required for their operation; This invention is designed for the pur os'e of greatly reducingthe cost of labor bot by' rendering it possible to use unskilled labor and by reducin v the time required for ramming up the modds, and at the same time to provide amachine which-while capable of being operatedby power will not require an extensive power plant, and can be run a l. vantageously without -a mechanical power plant at all. e

Referring now to the drawings it will be seen that an ordinary well-known type of flask-su porting and pattern-operating molding'mac nne is illustrated involving a frame A on" which a reciprocable pattern B is mounted, adapted to be operated through a stripping. plate M- or in any other d'esired' manner and to be held rigidly in position. while the sand ispacked by means of levers 4 connected with an operating handle J. On

lnachineiis. rigidly supporte [the flask which. may be ofany ordinary construction,

but 85 comparatively long-Ind row, because this invention .while capable of general use is somewhat more advantageous when used for flasks, of this general shape.

In the drawingsthe flask is shown as station-v ary. The sand D is placed in the flask and does not ordinarily need to be stricken ofl, although-this maybe done if desired. If there is a projecting part on the pattern,'a

bar L is placed in the sand above the pattern before the mo ld1ng operation is commenced, as shownin Fig. 2. This is then removed to leavefa groove or depression in the sand above the projecting part of the pattern, so

that as the sand is uniformly compressed in the flask there,v will not be a hard. spot inv contact with the said projecting portion.

Whether this isdone ,or not the next step in the operation ofthe device is to pass over the surface of the sand a heavy cylindrical smooth-surfaced roller E adapted to pcompress the sand entirely by its own weight.

' rectly by the and in the flask. It is This roller rests on the edges of the'flasl: and is supported entirely thereby while compressing the sand, except that on its first passage over the flaskit may be supported indiprovided Jwit'h flanges F located outside the edges of the flaskfor in proper position. i

The method-of First the roller is passed .onceover the flask from one end to the other to'form a preliminary compression and to progressively compress thesand againstthe pattern from one side. Thisgoperation is very complete as the roller compresses the sand uniformlyfrom one side of-thej flask. to the other, and also by its progressivesmovementsecures uniform compression from ,oneend to the other. If-

the sand is heaped. up very much onthe flask before the roller passes over it, as is indicated in Fig. 1,'the "roller may not rest-d-irectl'ron the edges of the flask during its first passage over, but afterthis is completed it is drawn back and then it rests-directly on the edges of the flask and compresses the sand down to a level with them. Itwill be seen that if on the first-passagerof theroller it compresses 'thesand on the near side of the pattern a little more firmly than on the far side, orif it has-any tendency to push the sand away from the far side this willbe entirely corrected on-the re verse motion of the roller, so that-a thorough,

complete, and uniform compression is se-- cured as has beenamply demonstrated in' practice. The roller may be operated in any desired way, but a means isshown extending substantially at right angles to the axis of the roller, and moving horizontally back and forth, consisting of arack Goperated by a pinion "H which may be turned by power or 'by hand as desired. When the rolleniis drawn away from the'flask, it is carried on tracks 0 located outside the flask substan? tially on a level" with the; top thereof and;

the purpose of keeping it oPeratiQnis .as"follows':

forward end may be secured in any desired way, but when supported by the blocks it is secured simply by removing and replacing of the top of the flask.

It willbe understood, of course, that while certain forms of patterns and flasks have them until track is brought to the level ,been shown, the invention is not limited to any particular form but it has been'found tobe particularly applicable to the molding of columns, ipes, and other long articles. 'It

will'be seen also that theflask may be supportedin any desired manner, but it is shown here as supported instationary position, the molding machine itself constituting means for rigidly supporting it. The pattern also is shown as rigidly supported in the flask during the molding'o eration by the link" motion connected wit the handle J. will be seen also that the heavy roller which the sand particles compactly into every crevice pr opening in the pattern, thereby methods heretofore employed, so that a casting can be made that will be substantially The sand parfree from roughness or scabs.

securing a mold which'is more nearly perfect than has been secured by any of the ordinary compresses the sand by its own weight forces ticles under the progressive rolling IGSSUI6 of the roller are forced one over anot er into the smallest de resslons 1n the pattern.

i lhile l have lustrated anddescribed a cer- ,tain form in which the invention has practi modifications may be made therein by any person skilled inthe artwithout departing from the scope of the lDYGDlBIODiLS'GXPI'QSSBCl in the claims.

herein'shown, but.

What I do claim is t combination of a ask, means for rigidly supporting a pattern in ,the bottom of theflask,

means for Withdrawing the pattern from the flask, and. a sandrammingzdevice comprising a heavy cylindricaljsmoothsurfaced roller uniiorm from one edg e of the flask to the nth r, the uniform portion thereof bemgof greater width than the interior width of the Cally been carried out, I am aware that many Therefore do not wish t'o be limited to all the features of construction Lln afoundr molding apparatus, the

iask andadapted' to roll over'the" flask to compress the sand on the pattern by'itsf own weight and supported entirely. by the top edges of the flask'while compressing thesand. 2 In a foundry molding-= machine, j the combination of a rigidly supported flask hav' ing sides and ends of the same height,a ate tern support-at the bottom thereof, said ask "and pattern-su port being separable fr 3 lt-O -each oth'er,lan aramnimg device "for-the mold comprising a cylindrical roller of uniform. diameter throughout its central portion, th e,ui1iform portion; of the roller projcting over'the. edgesof the flask, and resting -substafitially in contact with the tops of said edges whereby said roller can roll over the whole length of the flask and over the ends thereof wlthout being lifted; f

*3, i In'a sand molding'apparatus, the combination'of a flask, and a roller adapted to roll over the flask to compress t e sand therein to a level'surface 'andsup o'rted substantially;.infcontactwith"the e ges" ofthe flask 'bination of afia'sk,"'an

while compressing the"sand,'and meanslo substantially on a.-

cated .outside the flask level with'the top of the flask for supporting said rollerindependently of the flask, when the roller isnot in position for compressing the sand in the flas 4. In-asand-molding apparatus, the coma ieavy smooth-surfaced roller adapted to, roll over the flask to eompress'the sand entirely by its own weight and supported on the edges of the flask while compressing the sand, and vertically adjustbination of a. flask, a heavy. smooth surfaced "roller adapted tol-r'ollover the flask to compress the sand entirely by its own weight and supported onv the edges of the flask while compressing the sand, and means adapted to be aced on the sand'in-the flask and over Whlch said roller rolls for producing a groove or de res's ion inthe molding sand.

6; n a sand molding apparatus, the combination-of a flask, a heavy smooth-'surfaced-.'

roller adapted to roll over the flask to compress the sand, and means adapted to be placed on the sand in the flask and over which said roller rolls for producing a groove Ior depression in the molding sand.

. WALTER H. HOFMANN.

'itnesses:

' AGNES L. CLUNE,

C. SrnvENs. 

